Axle lift assembly

ABSTRACT

An axle lift assembly includes a vehicle configured to support a load. A slide assembly has a member that is movable along a longitudinal extent of the vehicle. The slide assembly is operable to secure the member relative to the vehicle at a select position along the longitudinal extent of the vehicle. A swing arm has a first end pivotally coupled with the member and an opposing second end biased away from the vehicle. The swing arm is configured to support a wheel assembly with a tire for contacting a ground surface. An actuator is operably interconnecting the member and the swing arm for raising the wheel assembly toward the vehicle to lift the tire away from the ground surface. The slide assembly and the actuator are operable to respectively adjust longitudinal and vertical positions of the wheel assembly relative to the vehicle for accommodating a condition of the load.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.14/189,469 filed on Feb. 25, 2014, entitled “AXLE LIFT ASSEMBLY,” whichis a continuation of U.S. patent application Ser. No. 13/966,789 filedon Aug. 14, 2013, now issued as U.S. Pat. No. 8,695,998, entitled “AXLELIFT ASSEMBLY.” U.S. patent application Ser. No. 13/966,789 claimspriority under 35 U.S.C. §119(e) to, and the benefit of, U.S.Provisional Patent Application No. 61/767,029, entitled “AXLE LIFTASSEMBLY,” filed on Feb. 20, 2013, the entire disclosure of which ishereby incorporated by reference.

FIELD OF THE INVENTION

The present invention generally relates to an axle lift assembly, andmore particularly, to an axle lift assembly for a vehicle that, in oneembodiment, is longitudinally slidable relative to a chassis of thevehicle and actuatable based on weight of a load carried by the vehicle.

BACKGROUND OF THE INVENTION

As businesses attempt to optimize inventory levels to meet variabledemand, it is common for modern industrial vehicles, including trucksand trailers, to be used for shipping a wide variety of load types andconfigurations. In general, it is advantageous to alter a vehicle'scarrying capacity by adding or removing trailers from the vehicle orusing alternatively sized trailers to accommodate the mass and volume ofthe load. For example, for loads with a smaller volume requirement, buta larger mass requirement, it can be beneficial to utilize a vehiclewith additional axles for dispersing the weight of the load over moretires. However, it can be inefficient to pull such a trailer when theadditional tires are unnecessary to disperse a light load, given thatadded tires increase friction and weight, as well as increase the costof roadway tolls. It can also be expensive to own and maintain severalvehicles and trailers for various load types and configurations.Nevertheless, to be competitive and profitable it is becomingincreasingly more important to reduce a vehicle's fuel consumption,unnecessary wear on tires, and improve other vehicle inefficiencies.

BRIEF SUMMARY OF THE INVENTION

According to one aspect of the present invention, an axle lift assemblyincludes a vehicle configured to support a load. A slide assembly has amember that is movable along a longitudinal extent of the vehicle. Theslide assembly is operable to secure the member relative to the vehicleat a select position along the longitudinal extent of the vehicle. Aswing arm has a first end pivotally coupled with the member and anopposing second end biased away from the vehicle. The swing arm isconfigured to support a wheel assembly with a tire for contacting aground surface. An actuator is operably interconnecting the member andthe swing arm for raising the wheel assembly toward the vehicle to liftthe tire away from the ground surface. The slide assembly and theactuator are operable to respectively adjust longitudinal and verticalpositions of the wheel assembly relative to the vehicle foraccommodating a condition of the load.

According to another aspect of the present invention, an axle liftassembly for a trailer that is configured to support a load includes amember configured to slidably couple with the trailer for adjusting alongitudinal position of the member relative to the trailer. A swing armhas a pivot end coupled with the member. An axle assembly is coupledwith the swing arm and is configured to support a tire. An air spring isdisposed between the swing arm and the member for biasing the axleassembly away from the member. A pneumatic actuator is operableinterconnecting the member and the swing arm. The pneumatic actuator isadjustable between a deflated position configured for the tire tocontact a ground surface and an inflated position configured to lift thetire away from the ground surface.

According to yet another aspect of the present invention, an axle liftassembly for a vehicle includes a member slidably adjustable along alongitudinal extent of the vehicle. A swing arm is pivotably coupledwith the member and biased away from the vehicle for supporting a tire.An actuator operably interconnects the member and the arm and isadjustable to raise the swing arm toward the vehicle for lifting thetire away from a ground surface.

These and other features, advantages, and objects of the presentinvention will be further understood and appreciated by those skilled inthe art by reference to the following specification, claims, andappended drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

In the drawings:

FIG. 1 is a top perspective view of a tandem axle assembly with airsuspension and having an axle lift assembly, according to one embodimentof the present invention;

FIG. 1A is a cross section view of a lug extending from a longitudinalbeam of the tandem axle assembly to engage an aperture on a vehicleframe member, taken at line IA-IA of FIG. 1;

FIG. 2 is a front elevational view of the tandem axle assembly;

FIG. 3 is a top plan view of the tandem axle assembly;

FIG. 4 is a bottom plan view of the tandem axle assembly;

FIG. 5 is a side elevational view of the tandem axle assembly;

FIG. 6 is a top perspective view of an axle, the associated trailingarms, and the brake assemblies of the axle lift assembly;

FIG. 7 is a fragmentary bottom perspective view of the axle liftassembly, showing a trailing arm, an air spring, and a pneumaticactuator of the axle lift assembly;

FIG. 8 is a fragmentary top perspective view of the axle lift assembly,showing a support bracket of the axle lift assembly;

FIG. 9 is an exploded top perspective view of the support bracket and apneumatic actuator of the of the axle lift assembly;

FIG. 10 is a side elevational view of the tandem axle assembly, showingthe axle of the axle lift assembly in a ground engagement according toone embodiment;

FIG. 11 is a side elevational view of the tandem axle assembly, showingthe axle of the axle lift assembly in a lifted position;

FIG. 12 is a flow chart of one embodiment of a system for controllingthe axle lift assembly; and

FIG. 13 is a flow chart of an additional embodiment of a system forcontrolling the axle lift assembly with a step of monitoring a tirepressure.

DETAILED DESCRIPTION OF THE EMBODIMENTS

For purposes of description herein, the terms “upper,” “lower,” “right,”“left,” “rear,” “front,” “vertical,” “horizontal,” and derivativesthereof shall relate to the invention as oriented in FIG. 1. However, itis to be understood that the invention may assume various alternativeorientations, except where expressly specified to the contrary. It isalso to be understood that the specific devices and processesillustrated in the attached drawings, and described in the followingspecification are simply exemplary embodiments of the inventive conceptsdefined in the appended claims. Hence, specific dimensions and otherphysical characteristics relating to the embodiments disclosed hereinare not to be considered as limiting, unless the claims expressly stateotherwise.

Referring to FIG. 1, the reference number 10 generally designates anaxle lift assembly of the present invention. In the illustratedembodiment, the axle lift assembly 10 is shown on a tandem axle assembly12 that is adapted for use on a vehicle, specifically a rear portion ofa semi-trailer. However, it is contemplated that the tandem axleassembly 12 may be used on other vehicles, such as trucks and trailerswith various axle arrangements, including semi-trucks, tractors,enclosed trailers, flat bed trailers, trailers with steerable axles, andother wheeled vehicles with more than two axles as generally understoodby one having ordinary skill in the art.

The illustrated tandem axle assembly 12, as shown in FIG. 1, includes arear axle assembly 14 and a front axle assembly 16, which mayconceivably be reversed in other embodiments. The front and rear axleassemblies 16, 14 each include a non-steerable axle 18 laterallyextending between a pair of trailing-arm air suspension systems.Conceivably, the rear axle assembly 14 may employ an alternativesuspension system. As illustrated, the front and rear axle assemblies16, 14 are extending between a pair of longitudinal beams 20 that extendalong a longitudinal extent of the trailer. The longitudinal beams 20are each slidably coupled with a corresponding frame member 22 thatsimilarly extends along the longitudinal extent of a lower portion of achassis of the trailer. The longitudinal beams 20 include a lockingassembly 24 to prevent sliding movement of the tandem axle assembly 12relative to the chassis of the trailer. The locking assembly 24 includesa pair of retractable lugs 26 that extend outward from the longitudinalbeams 20 to selectively engage a pair of a plurality of apertures 28that are spaced along a length of the frame member 22. Engagement of thelugs 26 of the locking assembly with the plurality of apertures 28restricts sliding movement of the beam 20 relative to the frame member22. It is conceivable that in alternative embodiments the lugs andapertures may be reversed or other means to restrict the longitudinalmovement of the tandem axle assembly 12 may be employed.

As further illustrated in FIG. 1A, a retractable lug 26 is shownextending laterally from the beam 20 to extend through an aperture 28 ofthe plurality of apertures on the frame member 22. An inboard portion ofthe retractable lug 26 is partially contained in a housing that holds aspring that biases the lug 26 laterally outward. The lugs 26 eachinclude a tension rod 30 (FIG. 1) that extends from the inboard portionthe lugs 26 to a central bar 32 that is longitudinally disposed betweenthe longitudinal beams 20. The central bar 32 is rotatably configuredwith cams that engage the tension rods 30, such that rotation of thecentral bar 32 moves the cams to draw the tension rods 30 inward andthereby pull the retractable lugs 26 inward to allow slidable movementof the tandem axle assembly 12 longitudinally relative to the chassis ofthe vehicle.

As shown in FIG. 2, the front axle assembly 16 includes a brake assembly34 coupled with the distal ends of the front axle 18. Accordingly, thedistal ends of the front axle 18 also include wheel assemblies 36 thatare configured to be releasably engaged by the brake assemblies 34 toreduce and cease rotation of the wheel assemblies 36. The wheelassemblies 36 include a tire for contacting a road or ground surfaceand, in one embodiment, a tire pressure sensor 38 for monitoring the airpressure of the tire. It is contemplated that the tires may include dualtires for increasing tire surface contact with the road surface. It isalso understood that the rear axle assembly 14 (FIG. 1) includes acorresponding wheel assembly 36 on the opposing side of the axle 18 thatmay also similarly include tire pressure sensors 38 and other relatedcomponents.

Referring now to FIGS. 3 and 4, the tandem axle assembly 12 includes anumber of cross members 40 that extend substantially orthogonallybetween the longitudinal beams 20. The central bar 32 that operates toretract the retractable lugs 26 from engagement with the frame member 22(FIG. 1A) is rotatably coupled between the cross members 40 proximatethe front axle assembly 16. An auxiliary pneumatic cylinder 42 includesan actuation shaft that is coupled to the central bar 32 with arotational coupling that surrounds a portion of the central bar 32 forrotating the central bar 32 upon actuation of the auxiliary pneumaticcylinder 42. It is contemplated that alternative actuation mechanisms,such as solenoids or electric motors, may be employed to engage anddisengage the plurality of lugs 26 with the apertures 28 in the framemember 22 (FIG. 1A).

As illustrated in FIG. 5, a single side of the tandem axle assembly 12is shown, although it is understood in the foregoing description thatthe opposing side of the tandem axle assembly 12 includes like parts,unless specified to the contrary. As shown in the illustratedembodiment, a support bracket 44 extends down from the beam 20 proximatethe front axle assembly 16. The support bracket 44 has an upper portion46 coupled with the beam 20 and a lower portion 48 pivotally coupledwith the upper portion 46. The lower portion 48 includes a platform 50longitudinally protruding toward the axle 18 for supporting a pneumaticactuator 52. More specifically, the platform 50 is defined on a rearwardend of the generally L-shaped lower portion 48 of the support bracket44. A trailing arm 54 of the front axle assembly 16 includes a first end56 pivotably coupled with the upper portion 46 of the support bracket44, above the pivotal connection between the upper and lower portions46, 48 of the support bracket 44. A cylindrical shock 58 is pivotablycoupled with and extends down from the longitudinal beam 20 proximatethe connection with the support bracket 44 to engage the axle 18proximate the trailing arm 54. It is contemplated that the supportbracket 44 may be a unitary bracket, an integral piece of thelongitudinal beam 20, or other conceivable geometric configurations thatincorporates a lift assembly 66.

The axle 18 on the rear axle assembly 14, as shown in FIGS. 5 and 6, isrotatably coupled with an intermediate portion 60 of the trailing arm54, between the first end 56 and a second end 62 of the trailing arm 54,in a substantially similar manner as the front axle assembly 16. Infurther similarity to the front axle assembly 16, the axle 18 of therear axle assembly 14 includes a sleeve for an axle shaft to rotatewithin, such that the intermediate portion of the trailing arm 54couples with the sleeve of the axle 18 to permit rotation of the axleshaft at the distal ends for corresponding rotation of the wheelassemblies 36. An air spring 64, or ride bag, is disposed between thesecond end 62 of the trailing arm 54 and the longitudinal beam 20 forreceiving the downward load from the tire riding on a road or groundsurface and for receiving, and in some instances absorbing, an upwardforce on the axle 18, such as impact forces from the tire hitting bumpson the road surface. The air springs 64 on both the front and rear axleassemblies 16, 14 are coupled with a substantially planar and circularsurface on the second end 62 of the trailing arm 54. The substantiallyplanar surface on the second end 62 of the trailing arm 54 is defined bya tear-shaped plate coupled with an upper surface of the trailing arm 54proximate the second end 62. It is conceivable that in additionalembodiments that the axle 18 and the air springs 64 may be alternativelycoupled with trailing arm 54 closer to the second end 62 or the firstend 56 of the trailing arm 54.

As shown in FIG. 5, the air spring 64 on the rear axle assembly 14, andconceivably also on the front axle assembly 16, includes an air pressuresensor 65 that monitors the air pressure of the corresponding air spring64. The air pressure sensor 65 may be used to monitor the weight of theload proximate the associated axle assembly by taking into considerationthe difference in air pressure of the air spring 64 between an unloadedstate and a loaded state. In addition, it is contemplated that the airsprings 64 on the front and rear axle assemblies 16, 14 (FIG. 5) mayjointly include an air pressure sensor that monitors the air springs 64of both axle assemblies.

Referring now to FIGS. 7-9, a lift assembly 66 is generally coupledbetween the trailing arm 54 (FIG. 6) and the longitudinal beam 20. Thelift assembly 66, according to one embodiment, includes a pneumaticactuator 52 that is disposed between the platform 50 longitudinallyprotruding from the lower portion 48 of the support bracket 44 (FIG. 5)and the trailing arm 54. More specifically, the pneumatic actuator 52includes a bearing block 68 on an upper surface of the pneumaticactuator 52. The bearing block 68 is configured to abut a bottom surfaceof the trailing arm 54 between the first end 56 (FIG. 6) of the trailingarm 54 and the axle 18. A guide arm 70 is coupled with the bearing block68 and extends to couple with the support bracket 44 at the pivotalconnection between the upper and lower portions 46, 48 of the supportbracket 44. The pneumatic actuator 52 is adjustable with compressed airbetween a deflated position 72 (FIG. 10) and an inflated position 74(FIG. 11). In the deflated position 72, as also shown in FIG. 8, thebearing block 68 may be out of contact with the trailing arm 54 and thetire on the associated axle 18 is in load bearing contact with the roadsurface, defining the ground engagement position 76 (FIG. 10), of theaxle 18, as further described below. In the inflated position 74, thepneumatic actuator 52 is inflated to raise upward from the platform 50on the support bracket 44 and put the bearing block 68 into contact withthe trailing arm 54, ultimately raising the axle 18 to a lifted position78 (FIG. 11) to elevate the tire from the road surface. When thepneumatic actuator 52 moves to the inflated position 74, the guide armrotates about the pivotal connection between the upper and lowerportions of the support bracket 44.

As further illustrated in FIG. 10, one embodiment of the lift assembly66 has the front axle assembly 16 in the ground engagement position 76and shows the lifted position 78 in fragmented lines. In the groundengagement position 76, the air spring 64 of the front axle assembly 16is pressurized to receive and absorb upward forces from the front axle18 (FIG. 7). As illustrated in FIG. 11, the lift assembly 66 isactivated to place the front axle 18 in the lifted position 78, alsoshowing the ground engagement position 76 in fragmented lines. In thelifted position 78, the air spring 64 of the front axle assembly 16 hasair released to depressurize and to allow the axle 18 to be moved towardthe longitudinal beam 20 a distance adapted to raise the associated tireon the front axle 18 away from the road or ground surface. The liftassembly 66 may be actuated between the ground engagement position 76and the lifted position 78, adjusting the pneumatic actuator 52 (FIG. 9)between the deflated and inflated positions 72, 74, respectively, byoperating the air system of the vehicle manually or automatically.Automatic actuation of the lift assembly 66 may be selected by a user,whereby a controller on the vehicle operates the lift assembly 66 usinga first automatic system, a second automatic system, or otherconceivable automatic actuation systems.

The first automatic actuation system, as illustrated in FIG. 12, isoperated by receiving input from the air pressure sensor 65 on the airsprings 64 of the rear axle assembly 14. Specifically, after the systemis powered up and pressurized air is available to operate the liftassembly 66, the system first checks to see if the parking brake of thevehicle is released. If the parking brake is released, then the systemdetermines that the vehicle is being operated. It is contemplated thatother indicators may be used to determine if the vehicle is beingoperated, such as a speed sensor, an ignition sensor, a GPS device, orother conceivable sensors or indications. Upon determination that thevehicle is being operated, namely the parking brake is released, the airpressure is monitored in at least one of the air spring 64 of the rearaxle assembly 14 by the air pressure sensors 65. It would also bepossible to alternatively or additionally monitor air springs 64 on thefront axle assembly 16.

As further shown in FIG. 12, when the lift assembly 66 is in thedeflated position 72, and the front axle 18 is in the ground engagementposition, such that the air spring 64 of the front axle assembly 16 isreceiving upward forces from the axle 18, the lift assembly 66 willautomatically move the front axle 18 to the retracted position byinflating the pneumatic actuator 52 to the inflated position 74 when theair pressure sensed by the pressure sensor 65 on the air spring 64 ofthe rear axle assembly 14 is below a lower threshold level. The lowerthreshold level is configured to be a pressure level that would indicatethe smallest payload weight that is best suited to be carried with boththe front and rear axles 18 supported on the ground. In other words,having an air pressure below the lower threshold level is indicative ofa payload weight acceptable for the rear axle to support without theneed to disperse the weight between the front and rear axles. Similarly,when lift assembly 66 is in the inflated position 74, or otherwisedeployed, and the front axle is in the lifted position, such that theair spring 64 on the front axle assembly 16 is not receiving upwardforces from the axle 18, the lift assembly 66 will automatically movethe front axle 18 to the ground engagement position 76 by releasing airin the pneumatic actuator 52 when the air pressure on the air spring 64of the rear axle assembly 14 is above an upper threshold level. Havingan air pressure above the upper threshold level is indicative of apayload weight large enough to exceed the suggested carrying capacity ofthe rear axle alone, and thereby require both the front and rear axlesto disperse the weight. The difference between the upper and lowerthreshold levels may be negligible, such that they can be referred togenerally as a threshold level; however the purpose of the difference isto prevent actuation of axle lift assembly due to minor variations inload weight that may be due to errors in the sensor 65 measurements,shifts in the load, bumps on the road, or other conditions that wouldcause minor variations in the sensor measurements, as generallyunderstood by one having ordinary skill in the art. The first actuationsystem also continues to monitor the parking brake to power down theautomatic actuation system when the parking brake is engaged. It isconceivable that the actuation system may be disabled manually by anoperator.

As shown in FIG. 13, the second automatic actuation system isalternatively operated with additional input from the tire pressuresensors 38. Again, the second actuation system first checks to see ifthe parking brake is released to determine whether the vehicle is beingoperated. When the parking brake is released, the tire pressure on therear axle assembly 14 is monitored with the tire pressure sensors 38. Ifthe tire pressure is outside an acceptable tire pressure range, asgenerally understood in the art as a range that causes damage to thetires or presents a risk of tire failure, the system does not allow thelift assembly 66 to automatically move the front axle 18 to the liftedposition 78. Similarly, if the front axle 18 is already in the liftedposition 78 and the tire pressure sensors 38 sense the tire pressure onthe rear axle assembly 14 to be outside the acceptable tire pressurerange, the front axle 18 is move to the ground engagement position 76 byreleasing air from the pneumatic actuator 52. Therefore, if the vehicle12 is operating solely on the rear axle 18 with low tire pressure, thefront axle 18 will lower to the ground engagement position 76 to provideadditional support to the vehicle 12 and disable automatic actuation ofthe lift assembly 66 until the tire pressure returns within theacceptable tire pressure range. Otherwise, if the tire pressure isacceptable, the system monitors the air pressure of the air springs 64with the air pressure sensors 65, similar to the first automaticactuation system, to determine, in view of the threshold level, whetherthe lift assembly 66 should move the front axle 18 between the groundengagement position and the lifted position. It is also contemplatedthat the tire pressure sensors 38 may be alternatively monitored in asimilar manner to the air pressure sensors 65 to determine the payloadweight for actuating the lift assembly 66 between the deflated andinflated positions.

It will be understood by one having ordinary skill in the art thatconstruction of the described invention and other components is notlimited to any specific material. Other exemplary embodiments of theinvention disclosed herein may be formed from a wide variety ofmaterials, unless described otherwise herein.

For purposes of this disclosure, the term “coupled” (in all of itsforms, couple, coupling, coupled, etc.) generally means the joining oftwo components (electrical or mechanical) directly or indirectly to oneanother. Such joining may be stationary in nature or movable in nature.Such joining may be achieved with the two components (electrical ormechanical) and any additional intermediate members being integrallyformed as a single unitary body with one another or with the twocomponents. Such joining may be permanent in nature or may be removableor releasable in nature unless otherwise stated.

It is also important to note that the construction and arrangement ofthe elements of the invention as shown in the exemplary embodiments isillustrative only. Although only a few embodiments of the presentinnovations have been described in detail in this disclosure, thoseskilled in the art who review this disclosure will readily appreciatethat many modifications are possible (e.g., variations in sizes,dimensions, structures, shapes and proportions of the various elements,values of parameters, mounting arrangements, use of materials, colors,orientations, etc.) without materially departing from the novelteachings and advantages of the subject matter recited. For example,elements shown as integrally formed may be constructed of multiple partsor elements shown as multiple parts may be integrally formed, theoperation of the interfaces may be reversed or otherwise varied, thelength or width of the structures and/or members or connector or otherelements of the system may be varied, the nature or number of adjustmentpositions provided between the elements may be varied. It should benoted that the elements and/or assemblies of the system may beconstructed from any of a wide variety of materials that providesufficient strength or durability, in any of a wide variety of colors,textures, and combinations. Accordingly, all such modifications areintended to be included within the scope of the present innovations.Other substitutions, modifications, changes, and omissions may be madein the design, operating conditions, and arrangement of the desired andother exemplary embodiments without departing from the spirit of thepresent innovations.

It will be understood that any described processes or steps withindescribed processes may be combined with other disclosed processes orsteps to form structures within the scope of the present invention. Theexemplary structures and processes disclosed herein are for illustrativepurposes and are not to be construed as limiting.

It is also to be understood that variations and modifications can bemade on the aforementioned structure without departing from the conceptsof the present invention, and further it is to be understood that suchconcepts are intended to be covered by the following claims unless theseclaims by their language expressly state otherwise.

What is claimed is:
 1. An axle lift assembly comprising: a vehicleconfigured to support a load; a slide assembly having a member movablealong a longitudinal extent of the vehicle, the slide assembly operableto secure the member relative to the vehicle at a select position alongthe longitudinal extent of the vehicle; a swing arm having a first endpivotally coupled with the member and an opposing second end biased awayfrom the vehicle, the swing arm configured to support a wheel assemblywith a tire for contacting a ground surface; and an actuator operablyinterconnecting the member and the swing arm for raising the wheelassembly toward the vehicle to lift the tire away from the groundsurface, wherein the slide assembly and the actuator are operable torespectively adjust longitudinal and vertical positions of the wheelassembly relative to the vehicle for accommodating a condition of theload.
 2. The axle lift assembly of claim 1, wherein the condition of theload includes at least one of a weight of the load carried by thevehicle and a distribution of the load over the longitudinal extent ofthe vehicle.
 3. The axle lift assembly of claim 1, wherein the slideassembly includes a locking mechanism between the member and the vehiclefor releasably engaging at the select position along the longitudinalextent to prevent movement between the member and the vehicle.
 4. Theaxle lift assembly of claim 3, wherein the locking mechanism includes aretractable lug on one of the member and the vehicle for engaging anaperture on the other of the member and the vehicle to prevent the axlefrom sliding longitudinally relative to the vehicle.
 5. The axle liftassembly of claim 1, further comprising: a support bracket coupled withthe member and protruding downward proximate the first end of the swingarm, wherein the actuator is operable between the support bracket andthe swing arm.
 6. The axle lift assembly of claim 5, wherein theactuator is located between the support bracket and the swing arm. 7.The axle lift assembly of claim 6, wherein the actuator abuts thesupport bracket and the swing arm.
 8. The axle lift assembly of claim 1,wherein the actuator is pneumatically adjustable between a deflatedposition with the tire contacting the ground surface and an inflatedposition with the tire lifted away from the ground surface.
 9. The axlelift assembly of claim 1, further comprising: a component operablebetween the wheel assembly and the member for monitoring a conditionindicative of a weight of the load carried by the vehicle, wherein theactuator raises the wheel assembly toward the vehicle to lift the tireaway from the ground surface when the component is indicative of theweight being less than a threshold weight.
 10. An axle lift assembly fora trailer that is configured to support a load, comprising: a memberconfigured to slidably couple with the trailer for adjusting alongitudinal position of the member relative to the trailer; a swing armhaving a pivot end coupled with the member; an axle assembly coupledwith the swing arm and configured to support a tire; an air springdisposed between the swing arm and the member for biasing the axleassembly away from the member; and a pneumatic actuator operablyinterconnecting the member and the swing arm, wherein the pneumaticactuator is adjustable between a deflated position configured for thetire to contact a ground surface and an inflated position configured tolift the tire away from the ground surface.
 11. The axle lift assemblyof claim 10, further comprising: a locking mechanism between the memberand the trailer for releasably engaging the member along a longitudinalextent of the trailer to prevent movement between the member and thetrailer.
 12. The axle lift assembly of claim 11, wherein the lockingmechanism includes a retractable lug on one of the member and thetrailer for engaging a select aperture of a plurality of aperturesspaced along the other of the member and the trailer to prevent the axleassembly from sliding longitudinally relative to the trailer.
 13. Theaxle lift assembly of claim 10, further comprising: a support bracketcoupled with the member and protruding downward proximate the pivot endof the swing arm, wherein the pneumatic actuator is operable between thesupport bracket and the swing arm.
 14. The axle lift assembly of claim13, wherein the actuator is located between the support bracket and theswing arm.
 15. The axle lift assembly of claim 14, wherein the actuatorabuts the support bracket and the swing arm.
 16. The axle lift assemblyof claim 13, wherein a lower portion of the support bracket includes asubstantially planar surface coupled with and supporting the actuator.17. The axle lift assembly of claim 10, wherein the pneumatic actuatoris inflatable to raise the axle assembly closer to the trailer from alowered position arranged for the tire to contact the ground surface toa lifted position for the tire to rise away from the ground surface. 18.The axle lift assembly of claim 10, further comprising: a componentoperable between the axle assembly and the member for monitoring acondition indicative of a weight of the load carried by the vehicle,wherein the pneumatic actuator is inflated to the inflated position whenthe component is indicative of the weight being less than a thresholdweight.
 19. An axle lift assembly for a vehicle, comprising: a memberslidably adjustable along a longitudinal extent of the vehicle; a swingarm pivotably coupled with the member and biased away from the vehiclefor supporting a tire; and an actuator operably interconnecting themember and the swing arm and adjustable to raise the swing arm towardthe vehicle for lifting the tire away from a ground surface.
 20. Theaxle lift assembly of claim 19, further comprising: a locking assemblyhaving a retractable lug coupled with the member for selectivelyengaging an aperture on a frame member of the vehicle to prevent themember from sliding relative to the frame member.
 21. The axle liftassembly of claim 19, further comprising: a support bracket coupled withthe member and protruding downward, wherein the actuator is operablebetween the support bracket and the swing arm.
 22. The axle liftassembly of claim 21, wherein the actuator is located between thesupport bracket and the swing arm.
 23. The axle lift assembly of claim22, wherein the actuator abuts the support bracket and the swing arm.24. The axle lift assembly of claim 19, wherein the actuator ispneumatically adjustable between a deflated position with the tirecontacting the ground surface and an inflated position with the tirelifted away from the ground surface.
 25. The axle lift assembly of claim19, further comprising: a component operable between the swing arm andthe member for monitoring a condition indicative of a weight of a loadcarried by the vehicle, wherein the actuator raises the tire toward thevehicle to lift the tire away from the ground surface when the componentis indicative of the weight being less than a threshold weight.